Performance and behavior characteristics of electronic devices are heavily influenced by the material of the device active regions. Or example, P and N channel transistors have performance characteristics that depend on the material of the channels. Choosing the appropriate channel material for the different transistor types is important in optimizing or at least enhancing device performance. For example, P channel transistors are known to have better hole mobility using a silicon channel with a (110) crystal surface orientation than a silicon channel with a (100) crystal surface orientation, whereas N channel transistors are known to have better electron mobility using a silicon channel with a (100) crystal surface orientation than a silicon channel with a (110) crystal surface orientation. P and N channel transistor mobilities also depend on channel composition. For example, gallium arsenide improves electron mobility over silicon but does not improve hole mobility.
Thus, there is a benefit in a device structure, as well as a method for making that device structure, that uses different materials for the channels of P and N channel transistors.